Title Page
Contents
LIST OF ABBREVIATIONS 14
ABSTRACT 16
Part 1. Synthesis of degradable silyl ether thiol/epoxy networks 18
Ⅰ. INTRODUCTION 19
1. General Introduction 19
2. Research objectives 21
Ⅱ. MATERIALS AND METHODS 25
1. Materials 25
2. Experimental methods 25
3. Instruments 29
Ⅲ. RESULTS AND DISCUSSION 31
1. Characterization of silyl ether thiol curing agent 31
2. Thiol-epoxy click polymerization of epoxy resin with silyl-ether thiol curing agent 32
3. Hydrolytic degradation of networks 44
Ⅳ. CONCLUSION 52
Part 2. A Low-Dielectric and Degradable Adhesive for High-Frequency Electronic Devices 53
Ⅰ. INTRODUCTION 54
1. Adhesive layer for high-frequency electronic devices 54
2. Research objectives 55
Ⅱ. MATERIALS AND METHODS 58
1. Materials 58
2. Experimental methods 58
3. Instruments 61
Ⅲ. RESULTS AND DISCUSSION 63
1. Characterization of an ASEA 63
2. Characterization of triazole adhesive layer 64
3. Hydrolytic degradation of the adhesive layer 66
Ⅳ. CONCLUSION 75
Ⅴ. REFERENCE 76
ABSTRACT IN KOREAN 84
Table 1. Thermomechanical characterization by DMA analysis of thiol/epoxy networks 43
Figure 1. Amount and source of microplastic abundance 23
Figure 2. (a) Schematic diagram to illustrate the degradation of the thermoset (b) The molecular structure of a degradation reaction 24
Figure 3. FT-IR spectra of silyl ether thiol curing agents for (a) Compound 1 (b) Compound 2 and (c) Compound 3 37
Figure 4. ¹H NMR spectra of silyl ether thiol curing agents 38
Figure 5. FT-IR spectra of before and after polymerization for (a) TPTG (b) MSTPG, (c) PSPTG, and (d) OSTPG 39
Figure 6. DSC analysis of thiol/epoxy network 40
Figure 7. TGA profiles of thiol/epoxy networks 41
Figure 8. DMA analysis of thiol/epoxy networks for (a) TPTG, (b) MSPTG, (c) PSPTG, (d) OSPTG 42
Figure 9. Weight % of network samples immersed in 1M NaOH for a certain period 45
Figure 10. Camera images of network samples immersed in 1M NaOH 46
Figure 11. ¹H NMR spectra of TPTG, TMPMP degradation products, and TMPMP 49
Figure 12. ¹H NMR spectra of MSPTG, compound 1 degradation products, and compound 1 50
Figure 13. ¹H NMR spectra of PSPTG, compound 2 degradation products, and compound 2 51
Figure 14. Structural of FCCL with limitation and requirement of the current adhesive layer 56
Figure 15. Structural of the adhesive layer during thermal curing 57
Figure 16. FT-IR spectra of step-by-step products of ASEA 67
Figure 17. ¹H NMR spectra of step-by-step products of ASEA 68
Figure 18. FT-IR spectra of before and after azide-alkyne click reaction 69
Figure 19. SEM analysis of (a) adhesive layer coated on copper foil (b) CCL sample without adhesive layer (c) CCL sample with adhesive layer 70
Figure 20. (a) Peel test graph and (b) Peel strength of the adhesive layer according to the type and ratio of the alkyne monomer 71
Figure 21. The dielectric constant of the adhesive layer according to the type and ratio of the alkyne monomer 72
Figure 22. Weight % of adhesive samples immersed in 1M NaOH for a certain period 73
Figure 23. Camera images of (a) adhesive layer and (b) CCL sample immersed in 1M NaOH 74
Scheme 1. Synthesis of thiols from mercaptoethanol and trichlorosilanes 27
Scheme 2. The mechanism of thiol-epoxy click reaction and generated network structures of TGMDA/PETMP/Silyl-ether thiol 28
Scheme 3. Synthesis of (a) an ASEA (b) a triazole adhesive monomer 62